Systems for ultrasound beam forming data control

ABSTRACT

Disclosed are systems and methods which efficiently control storage of and/or access to data which includes repetitive data or data which is used by different modes, processes, etcetera. Embodiments provide control for storage of and/or access to large amounts of data used in ultrasound system beam forming for image generation using a hierarchy of sequencers for controlling storage of and/or access to data. A frame sequencer may provide control at a frame level while an address sequencer is implemented to provide control at a data access level.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is related to co-pending and commonly assignedU.S. patent application Ser. No. 10/745,827, entitled “Ultrasonic SignalProcessor For A Hand Held Ultrasonic Diagnostic Instrument,” filed Dec.24, 2003; and Ser. No. 10/099,474, entitled “Balance Body UltrasoundSystem,” filed Mar. 15, 2002, the disclosures of which are herebyincorporated herein by reference.

TECHNICAL FIELD

The present invention relates generally to controlling storage of and/oraccess to data and, more particularly, to controlling storage of and/oraccess to ultrasound beam forming data.

BACKGROUND OF THE INVENTION

Ultrasound systems operable to provide images using transmission ofultrasonic energy are well known. Such systems typically employ atransducer assembly having an array of transducers where controlledexcitation of the transducers causes an ultrasound wavefront topropagate into an adjacent medium, e.g., a human body. The ultrasoundwavefront travels through the medium until reflected by an object orother variation in density of the medium experienced by the propagatingwavefront. The ultrasound system uses the portion of the reflectedultrasound energy received by the array of transducers to process animage.

Beam forming techniques (e.g., providing relative phase and/or amplituderelationships) are typically used with respect to the transducers of thearray of transducers in order to focus ultrasound energy whentransmitting and/or receiving ultrasound energy. For example, differentbeam forming parameters, setting forth the phase and/or amplituderelationship for each transducer of the array of transducers to be usedin forming the image, are used for each line (or ray) of an image frame.Additional information is generally used with respect to each such line,such as for image mode (echo, color, two dimensional, etcetera), imagezone (focusing depth), image resolution (number of lines, lineinterleaving, line increments), and the like.

In the past, the foregoing beam forming parameters and additionalinformation has been provided using a simple “brute force” technique.Specifically, a table having separate entries for each line of eachframe would be provided. The entries for a particular line would includethe beam forming parameters and additional information associated withthat line of the frame. In forming an image frame, the ultrasound systemwould step through the table entries associated with a selected frame toobtain beam forming parameters and additional information for each linethereof. Accordingly, if a frame consists of 512 lines, 512 entrieswould be provided in the table for that frame, with each entry includingall the beam forming parameters and additional information for theappropriate line. Additionally, each frame would have separate lineentries for that frame, irrespective of whether any of that informationwas common to another line or frame.

Use of the above tables provides a straight forward technique for beamforming data control as each frame is expressly defined by a set oftable entries. Accordingly, a new or different image mode, zone, orresolution may readily be implemented by a manufacturer of theultrasound device providing table entries defining each line of adesired image. Moreover, providing control with respect to the beamforming data and additional data is very simple as the data entries foreach line of a frame may be stepped through sequentially using commondirect memory access (DMA) techniques.

However, the foregoing suffers from several disadvantages. For example,the use of separate entries for each line of a frame as provided in thepast requires a large amount of memory to store beam forming parametersand additional information supporting various image modes, image zones,etcetera. Specifically, although some of the information, such as theimage mode, image zone, image resolution, etcetera, may remain unchangedfrom line to line, the separate entries for each line of a frame asimplemented in the past will discretely store such information for eachline. Moreover, a first frame, such as may be associated with a firstimage mode, image zone, image resolution, etcetera, will have discreteentries associated with each line thereof, a second frame, such as maybe associated with a second image mode, image zone, image resolution,etcetera, will have discrete entries associated with each line thereof,and so on. Accordingly, although some of the information, such as beamforming parameters, may be the same as between various lines of theframes, this information will be stored separately for each frame inwhich it is used.

From the above, it can be appreciated that techniques for beam formingdata control implemented in the past require large amounts of memory.Such large amounts of memory can require relatively large amounts ofspace in an ultrasound system, can consume relatively large amounts ofpower to operate, and can generate relatively large amounts of heat tobe dissipated by the ultrasound system. Such characteristics of largememories have typically not been an issue with respect to ultrasoundsystems as such systems are typically cart based configurations wheresize, power consumption, and thermal dissipation are not critical.

BRIEF SUMMARY OF THE INVENTION

The present invention is directed to systems and methods whichefficiently control storage of and/or access to data which includesrepetitive data or data which is used by different modes, processes,etcetera. Where large amounts of data is stored, techniques of thepresent invention may be used to provide reduction in memory used forstorage of data. Moreover, techniques of the present invention may beused to provide improved data transfer rates.

Embodiments of the present invention provide control for storage ofand/or access to large amounts of data used in ultrasound system beamforming for image generation. Ultrasound systems for which embodimentsof the present invention may be implemented provide for a variety ofimage modes (e.g., B mode, color Doppler, etcetera), image zones (e.g.,selectable image depths, multiple depth imaging, etcetera), imageresolutions (e.g., all lines, every other line, every third line, lineinterleaving, etcetera), and/or the like. Information, such as beamforming parameters and/or additional information, may be common betweenvarious lines in a frame, between frames of various modes, zones,resolutions, etcetera. Embodiments of the present invention operate toefficiently store and retrieve such data.

According to embodiments of the present invention, a hierarchy ofsequencers are used in controlling storage of and/or access to data. Forexample, an embodiment utilized with respect to an ultrasound systemimplements a frame sequencer to provide control at a frame level whilean address sequencer is implemented to provide control at a data accesslevel. Additional sequencers may be implemented between the abovementioned frame sequencer and address sequencer, such as a linesequencer to provide control at a line level, if desired.

A frame sequencer of an embodiment of the present invention providesoverall control with respect to a frame, such as to control the imagemode, the image zone, the image resolution, and the sequence of lines inthe frame. Frame sequencers of embodiments of the invention provide aninstruction based model in which looping and incrementing of variousframe parameters is implemented. Frame sequencers of embodiments of theinvention utilize very little memory in order to program the framesequencer for operation with respect to a particular desired image.Accordingly, frame sequencers of embodiments of the invention facilitatea reduction in the amount of memory utilized for beam forming, such ason the order of 200:1 to 500:1. Moreover, when an image mode or otherimage aspect is changed, a frame sequencer of embodiments of the presentinvention may be reprogrammed for operation with respect to the newdesired image quickly.

An address sequencer of an embodiment of the present invention providescontrol with respect to data for each line of a frame. Addresssequencers of embodiments of the invention provide an instruction basedmodel in which data addresses are computed on the fly to accessappropriate beam forming parameters and/or additional information whichis efficiently stored for use in various image modes, image zones, imageresolutions, etcetera. A multi-dimensional array or arrays of beamforming parameters and/or additional information is accessed by addresssequencers of embodiments of the invention. Address sequencers ofembodiments of the present invention provide for indirect addressing ofdata into such a multi-dimensional array, rather than being restrictedto direct sequential addressing associated with the tables used in thepast. Moreover, address sequencers of embodiments of the inventionprovide improved frame rates due to using less time to move data forlines.

From the above, it can be appreciated that techniques for beam formingdata control implemented in accordance with embodiments of the presentinvention reduce the amount of memory utilized and provide improvementsin data transfer rates without requiring more powerful/faster centralprocessing units or other modifications which significantly increasesize and/or power consumption. Accordingly, embodiments of the presentinvention provide benefits with respect to the use of space in anultrasound system, power consumption, and heat generated by anultrasound system. Such characteristics are particularly desirable withrespect to small or portable ultrasound systems, where size, powerconsumption, and thermal dissipation can become critical.

The foregoing has outlined rather broadly the features and technicaladvantages of the present invention in order that the detaileddescription of the invention that follows may be better understood.Additional features and advantages of the invention will be describedhereinafter which form the subject of the claims of the invention. Itshould be appreciated that the conception and specific embodimentdisclosed may be readily utilized as a basis for modifying or designingother structures for carrying out the same purposes of the presentinvention. It should also be realized that such equivalent constructionsdo not depart from the invention as set forth in the appended claims.The novel features which are believed to be characteristic of theinvention, both as to its organization and method of operation, togetherwith further objects and advantages will be better understood from thefollowing description when considered in connection with theaccompanying figures. It is to be expressly understood, however, thateach of the figures is provided for the purpose of illustration anddescription only and is not intended as a definition of the limits ofthe present invention.

BRIEF DESCRIPTION OF THE DRAWING

For a more complete understanding of the present invention, reference isnow made to the following descriptions taken in conjunction with theaccompanying drawing, in which:

FIG. 1 shows a block diagram of a system adapted according to andembodiment of the present invention;

FIG. 2 shows detail with respect to and embodiment of the memory controland memory of the system of FIG. 1;

FIG. 3 shows a flow diagram of operation of a frame sequencer of anembodiment of the present invention; and

FIG. 4 shows a flow diagram of operation of an address sequencer of anembodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Directing attention to FIG. 1, ultrasound system 100 is shown adaptedaccording to an embodiment of the present invention. Ultrasound system100 preferably operates to generate images using transmission/receptionof ultrasonic energy. Accordingly, ultrasound system 100 of theillustrated embodiment includes various circuits for the transmissionand reception of ultrasonic energy and the processing of signalsassociated therewith. Specifically, ultrasound system 100 of theillustrated embodiment includes transducer assembly 110,transmit/receive circuitry 120, front-end circuitry 130, signalprocessing/back-end circuitry 140, memory control 150, and memory 160.

Ultrasound system 100 of a preferred embodiment comprises a portable orhandheld ultrasound system configuration. Accordingly, ultrasound system100 may comprise a relatively small, light weight, self contained,system for providing ultrasound imaging operation. Embodiments ofultrasound system 100 implement a high level of integration, such as maybe provided using application specific integrated circuits (ASICs). Forexample, one or more of transmit/receive circuitry 120, front-endcircuitry 130, signal processing/back-end circuitry 140, memory control150, and memory 160 may comprise one or more ASICs. It should beappreciated that the illustrated delineation between circuitry is forreference to the illustrated embodiment and is not a limitation of theconcepts of the present invention. For example, front-end circuitry 130and memory control 150 may comprise a single ASIC, aspects of signalprocessing/back-end circuitry 140 may be provided on separate ASICs,etcetera, if desired.

Detail with respect to configurations of memory control 150 and memory160 according to embodiments of the invention, as well as interaction ofmemory control 150 and memory 160 with other circuitry of ultrasoundsystem 100, is provided herein. Transducer assembly 110,transmit/receive circuitry 120, front-end circuitry 130, and signalprocessing/back-end circuitry 140 operate in a substantiallyconventional manner and, therefore, their operation will not bedescribed in complete detail herein, except where such detail isparticularly useful in understanding concepts of the present inventionas incorporated in embodiments of memory control 150 and memory 160.Additional detail with respect to ultrasound systems, or circuitrythereof, as may be adapted according to embodiments of the presentinvention is shown in U.S. Pat. No. 5,722,412, entitled “Hand HeldUltrasonic Diagnostic Instrument,” U.S. Pat. No. 5,817,024, entitled“Hand Held Ultrasonic Diagnostic Instrument with Digital Beamformer,”U.S. Pat. No. 6,135,961, entitled “Ultrasonic Signal Processor for aHand Held Ultrasonic Diagnostic Instrument,” U.S. Pat. No. 6,203,498,entitled “Ultrasonic Imaging Device with Integral Display, U.S. Pat. No.6,383,139, entitled “Ultrasonic Signal Processor for Power DopplerImaging in a Hand Held Ultrasonic Diagnostic Instrument,” U.S. Pat. No.6,416,475, entitled “Ultrasonic Signal Processor for a Hand HeldUltrasonic Diagnostic Instrument,” U.S. Pat. No. 6,447,451, entitled“Mobile Ultrasound Diagnostic Instrument and Docking Stand,” U.S. Pat.No. 6,471,651, entitled “Low Power Portable Ultrasonic DiagnosticInstrument,” and U.S. Pat. No. 6,575,908, entitled “Balance BodyUltrasound System,” the disclosures of which are incorporated herein byreference.

Transducer assembly 110, having an array of transducers 111 a-111 n, isshown coupled to wave form generator 131 of front-end circuitry 130 viatransmit amplifiers 121 a-121 n and duplexers 123 a-123 n of transmitreceive circuitry 120. Accordingly, transducers of transducer assembly110 may be excited by a wave form provided by wavefront generator 131.Controlled excitation of transducers 111 a-111 n to cause an ultrasoundwavefront focused in a particular direction and/or to a particular depth(e.g., transmit beam forming) to propagate into an adjacent medium,e.g., a human body, is provided according to the illustrated embodimentby memory control 150 accessing appropriate beam forming parameters andadditional information from memory 160 and providing the foregoing tofront-end circuitry 130. For example, memory control 150 may providebeam forming parameters and additional information, such as image mode,image zone, and/or image resolution, to transmit and timing controlcircuit 134 in order to control appropriate ones of duplexers 123 a-123n to allow a wave form from wave form generator 131 to excite selectedones of the transducers and/or to control appropriate ones of transmitamplifiers 121 a-121 n to attenuate/amplify a wave form signal asprovided to corresponding ones of the transducers. The ultrasoundwavefront produced by transducer assembly 110 may thus be focused in aparticular direction, to a particular depth, etcetera and will travelthrough the medium until reflected by an object or other variation indensity of the medium experienced by the propagating wavefront.

Transducer assembly 110 is further shown coupled to signalprocessing/back-end circuitry 140 via duplexers 123 a-123 n and receiveamplifiers 122 a-122 n of transmit receive circuitry 120 and delaycircuit 132 and summing circuit 133 of front-end circuitry 130.Accordingly, when transducers of transducer assembly 110 are excited byultrasonic energy reflected by an object or other variation in thedensity of the medium, a received signal may be provided to signalprocessing/back-end circuitry 140, such as for presenting a graphicalimage, analysis, recording, etcetera. Processing and combining ofsignals as received by individual transducers of transducer assembly 110in order to generate a received signal focused with respect to aparticular direction and/or a particular depth (e.g., receive beamforming) is provided according to the illustrated embodiment by memorycontrol 150 accessing appropriate beam forming parameters and additionalinformation from memory 160 and providing the foregoing to front-endcircuitry 130. For example, memory control 150 may provide beam formingparameters and additional information, such as image mode, image zone,and/or image resolution, to delay circuit 132, summing circuit 133,and/or transmit and timing control circuit 134 in order to controlappropriate ones of duplexers 123 a-123 n to allow a received signalfrom selected ones of the transducers to be provided to correspondingones of receive amplifiers 122 a-122 n, to control appropriate ones ofreceive amplifiers 122 a-122 n to attenuate/amplify a signal as providedby corresponding ones of the transducers, to introduce/adjust relativephase delays with respect to the signals associated with particulartransducers, and/or to sum signals associated with particulartransducers into a beam formed signal. The received signal produced bytransducer assembly 110 may thus be focused in a particular direction,to a particular depth, etcetera for use by ultrasound system 100 toprocess an image.

From the above, it can be appreciated that control of ultrasound beamforming data by memory control 150 comprises control of different beamforming parameters, log forth the phase and/or amplitude relationshipfor each transducer of the array of transducers to be used in formingthe image, for each line of an image frame as well as additionalinformation used with respect to each such line, such as for image mode(echo, color, two dimensional, etcetera), image zone (depth), imageresolution (number of lines), and the like. Much of the foregoinginformation may be used in various different frames and/or lines. Forexample, frames associated with different image modes may have one ormore line formed using the same beam forming parameters. Likewise,different lines, whether associated with a same frame or differentframes, may use some of the same information, such as image zone, imagemode, etcetera. Accordingly, memory 160 of embodiments of the presentinvention is configured to efficiently store the foregoing information.Correspondingly, memory control 150 of embodiments of the presentinvention is configured to implement logic for an instruction basedmodel in which looping and incrementing of various frame parameters isimplemented and/or in which data addresses are computed on the fly toaccess appropriate information.

Memory control 150 of embodiments may be implemented in any number oftechnologies suitable for providing an instruction based model asdescribed herein. For example, memory control 150 may comprise a centralprocessing unit (CPU) operable under control of an instruction setdefining operation as described herein. However, embodiments of thepresent invention implement memory control 150 in one or more ASIC inorder to provide an implementation which uses relatively little space,has a relatively low power draw, and/or produces relatively little heat.

Memory 160 of embodiments may be implemented in any number oftechnologies suitable for providing data storage and access as describedherein. For example, memory 160 may comprise random access memory (RAM),read only memory (ROM), erasable programmable read only memory (EPROM),flash memory, magnetic memory, optical memory, and/or the like. However,embodiments of the present invention implement memory 160 usingnon-volatile memory having a relatively low power requirement, such asEPROM or flash memory.

FIG. 2 shows detail with respect to memory control 150 and memory 160 ofan embodiment of the present invention. The embodiment of memory control150 illustrated in FIG. 2 provides a hierarchy of sequencers for use incontrolling storage of and/or access to data. Specifically, framesequencer 251, for providing control at a frame level, and addresssequencer 252, for providing control at a data access level, are shownwith respect to memory control 150. It should be appreciated thatadditional or alternative sequencers may be implemented according toembodiments of the present invention. For example, a line sequencer,providing control at a line level, is disposed in the hierarchy betweenthe above mentioned frame sequencer and address sequencer according toan embodiment of the present invention.

Frame sequencer 251 of the illustrated embodiment of provides overallcontrol with respect to a frame, such as to control the image mode, theimage zone, the image resolution, and the sequence of lines in the frameby implementing looping and incrementing of various frame parameters.Accordingly, in operation according to an embodiment of the invention,frame sequencer 251 provides control with respect to other sequencers(e.g., address sequencer 252) of memory control 150 step through thelines of the frame, to implement the proper image mode, zone, and/orresolution, etcetera. For example, for every line of the frame, framesequencer 251 of a preferred embodiment provides parameters to othersequencers of memory control 150 with respect to what line is currentlybeing processed, what zone is being imaged, and what mode has beenselected. Those parameters are used by the other sequencers of memorycontrol 150 to cause the desired line to be processed appropriately.

FIG. 3 shows a flow diagram of operation of frame sequencer 251according to a simplified exemplary embodiment of the present invention.The flow diagram of FIG. 3 begins at block 301 wherein after aparticular frame (e.g., an image mode, an image zone, and an imageresolution) has been selected the appropriate frame parameters areloaded by frame sequencer 251. The foregoing frame parameters maycomprise a number of lines in the frame, a range of lines in the frame,a beginning line for the frame aperture, an ending line for the frameaperture, a base address for line beam forming parameters, a lineincrement amount, image mode information, image zone information, imageresolution information, and/or the like. At block 302 a line counter (L)is initialized to provide for incrementing through the lines of theframe. Correspondingly, the line counter (L) is incremented by a lineincrement amount of the frame parameters at block 303.

It should be appreciated that a line counter need not be incrementedeach time line information is controlled by frame sequencer 251,according to embodiments of the invention. For example, one or more ofthe aforementioned frame parameters may indicate that an image mode,such as Doppler, is to be utilized with respect to one or more lines.Accordingly, frame sequencer 251 may operate to cause multiple samplesto be taken at a same line to provide desired information, such asmovement, etcetera. Additionally, such a technique may be established asa nested loop to provide for sampling a number of lines multiple times(whether each line is sampled multiple lines before moving to the next,or a sampling of a series of lines is repeated multiple times), ifdesired.

At block 304, line parameters of the current line are provided to one ormore other sequencers of memory control 150. Such parameters maycomprise, and/or be utilized by the other sequencers to determine, thecurrent line, a base address for beam forming parameters of the frame,an offset for beam forming parameters of the current line, the imagemode for the current frame and/or line, the image zone for the currentframe and/or line, the image resolution for the current frame and/orline, etcetera. Using the foregoing parameters, an ultrasound pulse orpulses may be transmitted by transducer assembly 110 having a wave frontpropagating in a desired direction and/or focused to a desired depth, anecho may be received by transducer assembly 110 during a receive window,and the resulting signals beam formed to provide one or more linesignals for producing an image and/or for other processing by circuitryof ultrasound system 100.

At block 305 a determination is made as to whether the line counter (L)has been incremented to the last line of the currently selected frame.If the line counter (L) has not yet been incremented to the last line ofthe currently selected frame, processing returns to block 303 whereinthe line counter (L) is again incremented by the line increment amount.Accordingly, a loop is established for processing each line of acurrently selected frame. If, however, the line counter (L) has beenincremented to the last line of the currently selected frame, processingfalls out of the aforementioned loop to block 306.

At block 306 a determination is made as to whether the frame for whichprocessing has just completed remains selected. For example, a user mayselect a different image mode, a different image zone, etcetera, causinga different frame to be selected for processing. If the frame remainsselected, processing returns to block 302 wherein the line counter (L)is again initialized. Accordingly, a loop is established for againprocessing the selected frame, thus providing a series of frame updates,such as for processing moving images. If, however, the frame does notremain selected, processing falls out of the aforementioned loop toblock 307.

At block 307 a determination is made as to whether a new frame has beenselected. If a new frame has been selected, e.g., a user selected adifferent image mode, a different image zone, etcetera, processingreturns to block 301 wherein the appropriate frame parameters are loadedby frame sequencer 251. Accordingly, a loop is established forprocessing different frames. If, however, a new frame has not beenselected, processing according to the illustrated embodiment ends.

From the above, it should be appreciated that frame sequencer 251 of theillustrated embodiment utilizes very little memory in order to programthe frame sequencer for operation with respect to a particular desiredimage. Moreover, when an image mode or other image aspect is changed,frame sequencer 251 of embodiments of the present invention may bereprogrammed for operation with respect to the new desired imagequickly.

It should be appreciated that the foregoing exemplary embodiment ofoperation of frame sequencer 251 has been simplified in order to aid inthe understanding of the concepts of the present invention. Operation ofa frame sequencer of embodiments of the present invention may varysignificantly from that of the illustrated embodiment. For example, aframe sequencer of embodiments of the present invention may invokenested loops for controlling lines of various imaging modes and/orzones. According to one embodiment, a frame sequencer may provide forlines of a first mode (e.g., B mode) and lines of a second mode (e.g.,Doppler), where an image to be produced includes an image of one modesuperimposed upon an image of another mode, using a loop similar to thatdescribed above with respect to blocks 303-305 for the first mode andhaving a loop similar to that described above with respect to blocks303-305 for the second mode nested within the first loop. Whenimplementing such nested loops, the frame parameters loaded by framesequencer 251 preferably include parameters for each such loop/mode.Likewise, line counters, line incrementers, and/or other housekeepingfunctions are preferably adapted to track each such loop/mode.

Address sequencer 252 of the illustrated embodiment provides controlwith respect to data for each line of a frame using parameters suppliedby frame sequencer 251. For example, a preferred embodiment addresssequencer 252 provides an instruction based model in which dataaddresses within multi-dimensional array 261 of memory 160 are computedon the fly to access appropriate beam forming parameters and/oradditional information. Beam forming parameters and additionalinformation is preferably stored efficiently within multi-dimensionalarray 261 such that such information is available for use in variousimage modes, image zones, image resolutions, etcetera without havingbeen discretely stored for each such image modes, image zones, imageresolutions, etcetera. For example, multi-dimensional array 261 maystore one copy of beam forming parameters for each beam to be formed byultrasound system 100. These beam forming parameters are preferablyorganized in multi-dimensional array 261 such that the location of beamforming parameters and/or additional information of a desired beamconfiguration are readily locatable from a reference, such as a baseaddress. Accordingly, address sequencer 252 of embodiments of theinvention provides indirect addressing of data into multi-dimensionalarray 261, rather than being restricted to direct sequential addressingassociated with the tables used in the past.

Embodiments of the invention organize data in multi-dimensional array261 of memory 160 to match a register address space of front-endcircuitry 130. Accordingly, the starting address of data inmulti-dimensional array 261 may be calculated by address sequencer 252,with data beginning at this address being ordered to match the internaladdressing of front-end circuitry 130. Such embodiments facilitate veryefficient DMA transfers because blocks of contiguous addresses aredefined in both the source memory 160 and the target registers offront-end circuitry 130.

FIG. 4 shows a flow diagram of operation of address sequencer 252according to a simplified exemplary embodiment of the present invention.The flow diagram of FIG. 4 begins at block 401 wherein address sequencer252 receives parameters associated with the current line (L) from ahigher level sequencer. The higher level sequencer providing theparameters to address sequencer 252 may comprise frame sequencer 251discussed above. Additionally or alternatively, the higher levelsequencer providing the parameters to address sequencer 252 may comprisea sequencer disposed in the hierarchy between frame sequencer 251 andaddress sequencer 252, such as the aforementioned line sequencer.

At block 402 address sequencer 252 computes data addresses withinmulti-dimensional array 261 wherein appropriate line information isstored. For example, address sequencer 252 may utilize a base address,image mode information, image zone information, image resolutioninformation, and/or current line information to determine an addressrange of multi-dimensional array 261 in which the appropriate beamforming parameters and/or additional information for the current linemay be found. According to one embodiment, the foregoing addressdetermination is made by determining an offset from the base address ina first dimension of multi-dimensional array 261 associated with animage mode being used, determining an offset from the base address in asecond dimension of multi-dimensional array 261 associated with an imagezone being used, determining an offset from the base address in a thirddimension of multi-dimensional array 261 associated with a current line,and so forth. The resulting offset address may contain the actual lineinformation desired and/or may contain one Or more pointers to theactual line information desired, such as where some or all of the lineinformation desired is stored outside of multi-dimensional array 261(e.g., elsewhere within memory 160). The foregoing resulting offsetaddress may comprise multiple offset addresses, such as a first offsetaddress associated with beam forming parameters and a second offsetaddress associated with additional information for the current line.

At block 403 the appropriate information for the current line (L) isretrieved by address sequencer 252. As discussed above, such informationmay be retrieved from the address range determined with respect tomulti-dimensional array 261 and/or may be retrieved from memorylocations outside of multi-dimensional array 261.

At block 404 address sequencer 252 provides the retrieved lineinformation to circuitry of ultrasound system 100 for use. In theexample described herein, the retrieved information comprises beamforming parameters and/or additional information used intransmission/reception of ultrasound energy and thus may be provided tobeam forming circuitry, such as delay circuitry 132, summer circuitry133, and/or transmit and timing control circuitry 134. Such informationmay be provided to the foregoing circuitry directly by address sequencer252 or may be provided indirectly to the foregoing circuitry, such asthrough one or more higher level sequencers.

At block 405 address sequencer 252 reports completion of having providedthe desired information to the appropriate circuitry to one or morehigher level sequencer. For example, address sequencer 252 may providethe foregoing report to a line sequencer in order to notify the linesequencer that a transmit pulse of a current line may be accomplished.Thereafter, address sequencer 252 may repeat information retrieval andproviding steps for receive beam forming parameters and/or otherinformation and again report the conclusion of the cycle so that areceive signal may be processed.

After block 405 of the illustrated embodiment address sequencer 252 hascompleted processing with respect to the current line and thus the flowdiagram ends. However, a higher level sequencer, such as frame sequencer251, may increment the current line and thus again invoke the steps ofthe flow as set forth in FIG. 4.

From the above, it should be appreciated that address sequencer 252 ofthe illustrated embodiment enables beam forming parameters and/oradditional information used with respect to transmission/reception ofultrasound energy to be stored in memory 160 very efficiently. Inparticular, embodiments of the address sequencer provide intelligence tocalculate the addresses for stored blocks of data which are commonbetween different modes, lines, etcetera. Moreover, because theaddresses are determined on the fly according to embodiments of theinvention, frame rates may be improved due to it not taking as long tomove the appropriate data.

It should be appreciated that the foregoing exemplary embodiment ofoperation of address sequencer 252 has been simplified in order to aidin the understanding of the concepts of the present invention. Operationof an address sequencer of embodiments of the present invention may varysignificantly from that of the illustrated embodiment. For example, anaddress sequencer of embodiments of the present invention may invokedata address computation, information retrieval, and/or informationproviding steps in addition to or in the alternative to those shown,such as to provide different beam forming parameters and/or additionalinformation for a transmit and receive portion of the current line.

Although embodiments of an address sequencer of the present inventionhave been described with respect to their use in accessing informationused for beam forming, it should be appreciated that address sequencersof embodiments of the present invention may be utilized to provideinformation access with respect to various system operations. Forexample, a processor (e.g., CPU) of signal processing/backend circuitry140 may operate to move data, such as to save a JPEG image or do varioustypes of drawing on a video output. An address sequencer as describedherein could be applied to such a situation to allow the processor tomove image data by providing the address sequencer with appropriateparameters, such as an image number or type of image, and allowing theaddress sequencer to do calculations on its own in terms of what thesource and destination addresses would be and how much data to movearound.

Although the present invention and its advantages have been described indetail, it should be understood that various changes, substitutions andalterations can be made herein without departing from the invention asdefined by the appended claims. Moreover, the scope of the presentapplication is not intended to be limited to the particular embodimentsof the process, machine, manufacture, composition of matter, means,methods and steps described in the specification. As one will readilyappreciate from the disclosure, processes, machines, manufacture,compositions of matter, means, methods, or steps, presently existing orlater to be developed that perform substantially the same function orachieve substantially the same result as the corresponding embodimentsdescribed herein may be utilized. Accordingly, the appended claims areintended to include within their scope such processes, machines,manufacture, compositions of matter, means, methods, or steps.

What is claimed is:
 1. An ultrasound imaging system comprising: a memorycontaining a multi-dimensional array storing information for a number ofbeam forming parameters of a plurality of lines, wherein the beamforming parameters for each line are individually locatable based on oneor more offsets from a reference; and a memory control having ahierarchy of sequencers controlling access to said information stored insaid multi-dimensional array, wherein said hierarchy of sequencersincludes a frame sequencer configured to provide a number of lineparameters to be used in creating a frame of ultrasound data and anaddress sequencer that is configured to compute an address for locatingthe information in the multi-dimensional array for the beam formingparameters based on one or more offsets that are determined from theline parameters provided by the frame sequencer.
 2. The system of claim1, wherein the one or more offsets is associated with at least one of animage mode, an image zone, and an image line.
 3. The system of claim 1,wherein the beam forming parameters are stored in the multi-dimensionalarray at the address that is computed by the address sequencer.
 4. Thesystem of claim 1, wherein beam forming parameters are stored at alocation that is referenced by a pointer that is stored in themulti-dimensional array at an address that is computed by the addresssequencer.
 5. The system of claim 1, wherein said frame sequencerprovides control on a line-by-line basis.
 6. The system of claim 1,wherein said frame sequencer is initialized for use in different imagingmodes by providing parameters thereto.
 7. The system of claim 1, whereinsaid reference is a base address and the address for locating theinformation for the beam forming parameters for each line is determinedas an offset from said base address in at least one dimension of saidmulti-dimensional array.
 8. The system of claim 1, wherein saidhierarchy of sequencers are implemented in one or more applicationspecific integrated circuits.
 9. The system of claim 1, wherein saidultrasound imaging system comprises a portable diagnostic ultrasoundinstrument.
 10. The system of claim 1, wherein said multi-dimensionalarray comprises at least a three dimensional array.